While I am usually very skeptical with any kind of "structural logic" in our work and prefer to think instead more in terms of nonlinear system dynamics within the complexities of human motor organization, there are few exeptions in which I have come to agree to linear mechanical relationships. Most of them deal with gravity and its long-term effect on human structure. The following article, taken from a recent class handout of mine, is one example.

In the practice of Rolfing as well as in several other methods of bodywork it is not uncommon to experience the following scene: the practitioner discovers a pelvic torsion in the client. After successfully unwinding it (with usually either direct or indirect technique) the pelvis does indeed look more balanced on the table. But when the client stands up, the trunk and spine are now suddenly less good balanced than before; sometimes an underlying scoliotic pattern becomes more apparent. The question then comes up: Has the practitioner done something wrong, or something disintegrating to the structure? Or is it an acceptable sign of a necessary "healing crisis" (like in homeopathy and some other natural healing practices)? Or is it a sign of "a beautiful unwinding" of some hidden deeper patterns that are now surfacing and which we gladly appreciate since we can now work with them? This article will explore some anatomical relationships in order to help us to decide.

A pelvic torsion is usually defined as an intrasegmental pelvic pattern in which one ilium is tilted more anterior in relation to the other. Another way to say it is that one ilium is tilted more anterior and one more posterior in comparison with each other. For reasons not totally understood by me most torsions are - according to several published studies - "right anterior" (i.e. right ilium anterior & left ilium posterior in comparison with each other). When the ilium tilts more forward this brings the anterior superior iliac spine (ASIS) more anterior & inferior (and in most cases also more lateral). The ischial tuberosity will go more posterior and superior (and in most cases more medial). The posteriorly torqued ilium will perform the opposite changes. So far so good.

Let's now look at the relationship between acetabulum and sacroiliac joint. Their distance form each other won't change of course. But what can change is what I call "the vertical distance" between them; i.e. the difference in height between them.

1)

As you can see in the enclosed illustration an anterior rotation of the ilium will increase the vertical distance between the sacroiliac joint and the head of the femur. A posterior rotation of an ilium will decrease the vertical distance between the sacroiliac joint and the caput femoris. (Hint: Please check the meaning of the last two sentences - and especially of the words "vertical distance" - at the above illustration before you continue reading. Otherwise you run a considerable chance of missing the main point of this article.).

Imagine now some outside force (e.g. an accident) putting such a pelvic torsion into the body. How would this influence the overall alignment of the person standing in the gravitational field? Obviously the position of the sacrum will be influenced by this. The sacral base will be moved higher on the side of the anterior rotated ilium. In other words the base of the spine will be tilted towards the side of the posterior rotated ilium. Supposing that the sacral base can be either seen as an important support for the spine or at the least as an important indicator for the pelvic support for the spine above, we will now quite likely see a trunk pattern with less a good vertical alignment than before. This is of course all based on the assumption that the height of the top of the femur is the same on both legs.

Now imagine a healthy person standing with her pelvis on top of two legs where one head of the femur is higher than the other. The reasons for this could be many: a higher arch in one foot which might be more supinated than the other, or for example a slightly different length of the femur or tibia, the two longest bones in the body (be it because of the fact that bone growth rates are never one-hundred-zero-zero-percent exact and symmetrical - just look at the asymmetrical faces of people -, or be it because of a previous fracture of one leg). A pelvis with no previous torsion between its ilii will be tilted now with the acetabulum downward on the side of the lower femoral head. This will tend to tilt the sacrum to that side and make it quite difficult for the person to maintain a good balance with its trunk above. One way to cope with it (and not an unintelligent one) will be to drop the sacroiliac joint a bit lower on the side of the higher acetabulum and a bit higher on the other side in order to decrease the sideways tilt of the sacrum. We know from orthopedic measurements that a lot of weight is transmitted through those joints, therefor such a compensatory torsion will be quite easily achieved if the person tries to keep her trunk as evenly as possible balanced over her legs. The weight of her trunk will simply tend to rotate one sacroiliac joint further down. Looking at the above first illustration we understand that this will move the ASIS forward on one side and backwards on the other, but it will also be quite successful in horizontalizing an important base of support for the trunk.

What follows is quite simple. If a person is not complaining of any sacroiliac pain and if our main job continues to be to improve her overall alignment with gravity, then we should look at the sacral base in standing before derotating a pelvic torsion. If in a standing client the sacral base is higher on the side of the anterior rotated ilium, then it's probably useful for us as structural integrators to work on getting the torsion out of the pelvis.

If the sacral base is lower on the side of the anterior rotated ilium, then it is probably a good idea to leave the torsion as it is, since gravity as the therapist has been doing already a better job than we would (Fig.3).

I have watched this several times, even with several advanced bodyworkers that I know in our field as well as in osteopathy, chiropractic, etc.: A practitioner discovers a pelvic torsion in a client lying on the table and works on getting it out. So the pelvis looks more balanced aesthetically to the practitioner when lying on the table. But when the client stands up her upper body is now less balanced than before. Sometimes the practitioners then start to work on the trunk in order to correct it, sometimes they call it a healing crisis, or even worse "a beautiful unwinding". But they simply forgot to relate the pelvic torsion to gravity before trying to correct it, and by doing so they disintegrated the body actively themselves. Luckily "gravity as the therapist" will be usually quite successful to retain the previous pelvic torsion again after a few minutes of walking around or after walking down some stairs. So I don't think that any serious damage is usually done in those manipulations, - but it is simply a waste of time and energy.

What are the best ways to diagnose a pelvic torsion and to diagnose the position of the sacral base? Put a finger on the ASIS and another on the Posterior Superior Iliac Spine (PSIS) of the right ilium and compare their height in a standing client. (Note: The firmer you palpate the PSIS the more exact will you be able to locate it ). Then do the same with the ilium on the left side. This is simple to do and is a reliable indicator for a pelvic torsion pattern. Then look from behind at the so-called "dimples" in the skin over the sacrum and compare their height from the floor. Their relative positions are a fairly reliable indicator for the position of the sacral base. You could also look at any visible side-tilt of the lower portion of the lumbar spine and include that in your picture.

Doing this you will find out that it is actually not so uncommon to see a "structurally intelligent" pelvic torsion where the sacroiliac joint has simply dropped down on a slightly lower femoral head. And of course there are also cases where a "structurally unintelligent" pelvic torsion (originating often by forceful outside events) has pushed the sacrum higher on one side and thereby decreased the structural integration of the whole person.

To sum it up: Except in cases where sacroiliac pain conditions are more important than overall structural alignment or in cases with some rare but extreme side/side asymmetry fixations above, just follow this simple rule of thumb:

When the sacral base is more superior on the side of the anterior rotated ilium: work on derotating the pelvic torsion.

In all other cases2: leave the torsion as it is.

"When you force a local misaligned area into line, you only shift the strain.()This is what manipulators call a chronic lesion.A guy gets his back or hip out of order and goes to a manipulator, who adjusts it.He says `Oh, that's wonderful!', but he goes down the stairs and by the time he's on the street it's back again.()Gravity is the only tool that we use. I think my experience justifies making this very broad assumption.Gravity is the only tool that deals with chronic situations in the body."